eNOS is a significant source of vascular wall NO production and circulating NO.

<p>a) ESR spectrum of NO-Fe-(DETC)₂ in aortas of apoE^−/− and apoE^−/−/eNOS^−/−. Bold lines indicate apoE^−/−, stripped lines apoE^−/−/eNOS^−/− and patterned lines buffer/spin trap alone. Arrows show the typical 3 peaks NO-Fe-(DETC)₂ signal. b) Vascular NO production in C57BL/6J (n = 12), eNOS^−/− (n = 8), apoE^−/− (n = 14) and apoE^−/−/eNOS^−/− (n = 15), *p≤0.01, **p<0.001, ***p<0.0001). c) Vascular NO production with NOS inhibition using L-NAME in apoE^−/− (n = 11) and apoE^−/−/eNOS^−/− mice (n = 16), *p<0.01, ***p<0.0001. d) Nitrosyl hemoglobin concentration of blood samples from apoE^−/−/eNOS^−/− (n = 11) vs. apoE^−/− controls (n = 13, *p = 0.01).